Turbodrill



TURBODRILL 2 Sheets-Sheet 1 Filed Jan. 15, 1960 .IVILI I Maly 19, 1964 AG. P. LAGACHERIE ETAL TURBODRILL 2 Sheets-Sheet 2 Filed Jan. 15, 1960 B7' DEAN, MRBANK l #msc/4.

@TTIRMEYS United States Patent O 3,133,603 TURBODRILL Guy Pierre Lagacherie, Grenoble, Isere, and Jean-Pierre Lapeyre, Echirolles, Isere, France, assignors to Etablissements Neyr'pie (Ateliers Neyret-Beylier et Piccard- Pictet), a corporation of France Filed Jan. 15, 1960, Ser. No. 2,671 Ciaims priority, application France Jan. 22, 1959 1 Claim. (Cl. 175-107) The present invention relates to a turbo-drill or fluiddriven turbine comprising a xed tubular body, a shaft rotating inside said body, carrying a rotary drill bit at its lower extremity, a bearing at the lower part of the body for the rotary mounting of the said shaft in said body, a source of uid under pressure at the upper part of the device, turbine blades on said body and on said Shaft and receiving the fluid delivered from said source so `as to rotate the rotary shaft carry-ing the drill bit, a chamber disposed on the downstream side of the turbine blades and receiving the uid passing out from said blades, the said bearing being adjacent to said chamber, and a passage in a lower part of the said shaft leading from said chamber and opening in the vicinity of the drill bit.

An interaction is produced between the How of irrigation or drilling fluid to the tool and the irrigation flow, known as the leakage flow from the lower bearing. lf the drill bit has small -irrigation orifices, as is particularly the case when working with a jet-bit, the loss of pressure through the said orifices is large, `which makes it necessary to provide a high pressure at the level of the bearing, thereby increasing the leak-age flow from the bearing.

Since the fluid employed is mud charged with abrasive particles, the wear in the bearing is increased and the latter deteriorates rapidly. It is however necessary to maintain the jet effect through the orifices of small diameter in the drill bit, since the efficiency of jet bits is higher.

The present invention has for its object a turbo-drill of the type indicated above, in which the jet effect in the vicinity of the drill bit is important so as to give a good efficiency, while Iat the same time the pressure in the vicinity of the bearing is reduced so as to minimize the leakage flow through this bearing.

In :accordance with the invention, a turbo-drill device of the kind indicated `above is especially characterized in that a second passage is formed in the rotating shaft, is supplied directly yfrom Ithe source of fluid under pressure, and by-passes part of the ma-in flow with regard to the turbine.

In one form of construction, the first passage opens into the vicinity of the drill bit through a first outlet separate lfrom a second outlet through which the second passage opens into the vicinity of the tool, the first outlet being of large section in order to prevent .any excess pressure in the said chamber and thereby to avoid any excess feed of irrigation fluid to the said bearing, whilst the second outlet is of small section so as to produce powerful jets in the vicinity of the drill bit. The rst outlet of large section is central. lt is through this outlet that the large output Iof iiuid from the turbine passes out to provide a washing and evacuation action of cuttings from the bore. The second outlet with orifices of small section, which receives fluid at high pressure, produces jets with a high kinetic energy which not only complete the action of the tool by their impact effect on the cutting front but also the washing effect of the large-flow central orifice.

`In an alternative form of the invention, both the first and second passages have a single common outlet of Patented May 19, 1964 ICC small sect-ion in the vicinity of the drill bit in order to produce powerful jets, the junction of the two passages on the upstream side of the common outlet comprising a nozzle of the second passage delivering into a venturi of the first passage, so that the said chamber is relived of any excess pressure, thereby preventing any excess supply of irrigation fluid to the said bearing.

Forms of construction of the invention are described below by way of example, reference being made to the accompanying drawings, in which:

FIG. l is a view in longitudinal cross-section of a turbo-drill according to the invention, in which the two iiuid passages have separate outlets in `the vicinity of the drill bit;

FIG. 2 is a view in longitudinal cross-section of an alternative form of turbo-drill in accordance with the invention, in which the two fluid passages have a common outlet in the vicinity of the drill bit.

Reference will first be made to FIG. l, in which there is shown at 10 the xed tubular body of the drilling device, at 11 the shaft rotating with respect to the fixed body 10 and carrying the triple cone drill bit 12 at its lower extremity, at 13 a conduit coupled to a source of fluid under pressure at the upper part, at 14 the turbine blades disposed between the units -10 :and `11 and receiving the fluid issuing `from the conduit 13 in order to rotate the shaft 11 which carries the drill bit 12, at d5 =a chamber `disposed on the downstream side of .the turbine 14 and rece-iving the fluid passing out of the turbine 14, at 16 a bearing between the units 10 and 11, adjacent to the chamber 15 so -as to be `irrigated by the fluid from the said chamber, at 17 a first passage in a lower part of the -shaft 1l, leading from the chamber 15 at 18 and delivering at 19 in the vicinity of the drill bit 12, and at 26 :a second passage formed in the shaft 11 supplied directly -from lthe conduit 13 and opening at 21 into the vicinity of the drill bit 12.

The dirst passage 17 i-s formed between a bore in the shaft 11 and a tube 22, the interior of which forms the second passage 20. The tube 22 is held in position by means of a shoulder 23 and a clamping sleeve 24. The tube 22 is coupled in la fluid-tight manner to a distribution piece 25, which comprises the outlets 19 and 21 and is fixed by means of a shoulder 26 by the gripping action of the tool 12 on the sleeve 24. Sealing joints are provided at 27, 2S `and 29.

The drilling fluid reaches the upper part of the device through the conduit 13, following the arrow F, and is directed on the one hand into the blades of the turbine 14 in the direction of the :arrows F1 towards the chamber 15 so as to follow the first passage 17, and on the other hand in the direction of the arrow F2 in the tube 22 which forms the second passage 20.

The uid from the turbine 14, which is admitted at a high rate of flow from the chamber 15 at 18 into the first passage 17, circulates through this passage in the direction of the arrows F', and reaches a central bore 30 in the distribution piece 25, the end of which forms the outlet 19. The latter is of large section in order to ensure a high rate of flow `for the irrigation of the drill bit 12 and the evacuation of the cuttings from the bore. This large section of the outlet =19 has the additional effect of causing only a low pressure in the chamber 15, so that lthe leakages of uid through the bearing 16 are small, any excessive wear of the bearing 16 being thus prevented.

The iiuid admitted at high pressure to the second passage 20 circulates in this passage in the direction of the larrow F2 and passes from thence into three jet channels 31 of the distribution piece 25, the end nozzles 32 of which form the outlet 21. Each nozzle 32 is calibrated and interchangeable, and has a small section which en- 3 ables the flow of each jet to be regulated at 1:2. The rates of liow 11:2 are relatively small with respect to the flow Fl which passes through the central outlet 19, and act on the cutting front by dissipation of kinetic energy. Although the small section of the outlet 21 formed by the nozzles 32 gives rise to a considerable back-pressure above the drill bit, this back-pressure is not transmitted to the bearing 16 since the latter is separated from the fluid tiow F2 by the tube Z2.

By virtue of :the combined action of the two fiows F1 and F2, it is clear `that there is obtained a powerful cleaning faction on the tool Vand a considerable jet effect which substantially improves the efiiciency of the tool without giving rise at 15 to troublesome back-pressures on the bearing 16 of the turbine.

Reference will now be ma-de to FIG. 2, in which the yarrangement is similar to that which has been described above with reference to FIG. 1, lbut in which the two passages 17 and 20 do not have their openings in the vicinity of the drill bit 12 in the form of two separate outlets 19 and 21, but open into the vicinity of the drill bit 12 through a common outlet 33 formed by calibrated interchangeable nozzles 34 of small section so as to produce jets. The junction of the two passages 17 and 20 on the upstream side of the common outlet 33 comprises a nozzle 35 of the second passage 20 discharging into a venturi 36 of the first passage 17 so as to induce an ejector operation.

The drilling fluid reaches the upper part of the drilling device through the conduit 13 in the direction of the arrow F, and is directed on the one hand into the blades of the turbine 14 following the arrow F1, and on the other hand into the conduit 20 in the direction of the arrow F2.

The fluid passing out of the turbine 14 is delivered into the chamber 15 which irrigates the bearing 16. It is sucked ,through the orifices 18 by the ejector effect produced by the uid discharged at high speed through the nozzle 35 towards `the piece 36. In the divergent portion 37 of the piece 36 there is produced a pressure greater than the pressure inside the chamber 15.

The whole of :the fluid F1 from the turbine and the direct fluid F2 is :therefore at a considerable pressure at the outlet of lthe divergent 37, which enables the fluid to be violently projected on to the cutting front through Ithe intermediatry of the calibrated nozzles 34, while the pressure, which remains small at 15, is such that the leakages through the bearing 16 are themselves small, almost the entire qauntity of drilling fiuid being utilized on the cutting front.

IIt will of course be understood that the invention is in no way limited -to the forms of construction described and shown, but includes all their `alternative forms.

What we claim is:

A turbo-drill device comprising a stationary substantially vertical tubular body, a bearing at :the body lower end, a shaft coaxially spacedly extending in said body and mounted for rotation through said bearing in said body, said shaft having an upper end inside of said body `and a lower end outside of said body, a first fluid conduit means between said shaft and said body having a first fluid annular inlet between said shaft upper end end said body, turbine blades on said shaft and on said body extending in said first conduit means for rotating said shaft, a first chamber disposed on the downstream side of said blades in said first conduit means, said first chamber being adjacent to said bear-ing for lubricating said bearing by the first chamber iiuid, second conduit means in said shaft having a second fluid inlet at the shaft upper end and a fluid outlet at the shaft lower end, said second conduit means having a first conduit portion adjacent to said second inlet, ya second chamber surrounding at least :a lower part of said first conduit portion, a venturi-shaped second conduit portion connected with said second chamber, said first conduit portion having a discharging nozzle lower end located within said venturishaped second conduit portion, and a third conduit portion connected With said second conduit portion and adjacent to said outlet, fluid passage means between said :first chamber and said second chamber, fluid feeding means -for fully feeding fluid simultaneously to both inlets, and a drill bit at the shaft lower end operatively cooperating with fluid jets discharged `from said outlet.

References Cited in the file of this patent UNITED STATES PATENTS 11,482,702. Scharpenberg Feb. 5, 1924 2,380,112 Kinnear July 110, 1945 2,815,931 Williams Dec. 10, 1957 2,879,032 Whittle Mar. 24, 1959 2,890,859 Garrison June 16, 1959 2,910,273 Bon Oct. 27, 1959 2,944,792 Gros July l2, 1960 2,963,099 Gianelloni Dec. 6, 1960 3,077,937 Tiraspolsky Feb. 19, 1963 FOREIGN PATENTS 1,168,061 France Aug. 25, 1958 

